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1.
D2D(device to device)作为5G通信的核心技术,在满足用户通信需求与提高用户连通数量等方面具有至关重要的作用。针对传统复用算法的系统中断概率过高和用户资源消耗较大的问题,提出一种基于穷举搜索的D2D资源分配算法。该算法引入穷举搜索法初步确定用户发射功率;同时参考蜂窝与D2D用户状态以确定复用组合;应用调整功率步骤降低中断概率。仿真结果表明,小蜂窝用户数时基于穷举搜索的D2D资源分配算法相比于传统算法,在多D2D用户数情况下的连通概率平均提高了15.7%,用户资源消耗平均降低了10.5%。  相似文献   

2.
以alpha-beta剪枝算法为研究对象,提出一种基于alpha-beta剪枝和概率剪枝因素相结合的概率剪枝算法,来解决博弈树搜索问题。利用概率剪枝算法,可减少博弈树搜索深度,从而加快搜索进程。  相似文献   

3.
在PBIL算法及自私基因算法的基础上,提出了一个适应性更广、搜索能力更强的优化搜索算法。该算法从各基因位的初始等位基因概率出发,通过一系列概率采样、选择与搜索、概率修正等操作,使搜索空间逐步收敛于最优点。该算法既吸取了遗传算法的群体搜索的特点,又吸收了局部搜索算法的局部搜索能力强的优点。最后介绍了该算法在图论中的几个应用实例。  相似文献   

4.
基因学习算法解图的着色问题   总被引:1,自引:0,他引:1  
本文在PBIL算法及自私基因算法的基础上,提出一个适应性更广、搜索能力更强的优化搜索算法:基因学习算法。该算法从各基因位的初始等位基因概率出发,通过一系列的概率采样、群体选择与局部搜索、概率学习等操作,逐步缩小概率搜索空间,直至收敛。本文将该算法用于求解图的着色问题,取得了非常好的结果  相似文献   

5.
根据柔性车间调度问题提出基于解空间距离聚类和变邻域搜索的粒子群算法.在粒子群算法基础上采用贪婪策略引入变邻域搜索方式,即调整关键路径上最大关键工序的机器位置,调整关键路径上工序相对位置变化,加强局部搜索能力;根据机器加工工序的空间距离,采用K-means聚类得到机器加工工序“优良个体”,加大局部搜索性能.同时对于粒子群算法速度更新采用局部停滞策略,保留局部片段相对位置不变特性.通过实验仿真,优化算法取得了较好的效果,与一般的粒子群算法相比较收敛速度迅速且性能良好.  相似文献   

6.
针对置换流水车间调度问题(PFSP)的特点,提出一种基于工件加工位置与连接概率相结合的混合分布估计算法。该算法将工件位置概率与工件的连接概率结合在一起,作为新一代种群的生成概率从而使得进化趋势更加合理化。为了提高局部搜索能力,算法引入了启发式方法提高初始解质量,优化了邻域搜索策略。同时引入了变异操作及限定操作来提高算法全局搜索能力。实验结果表明,该算法在求解置换流水车间调度问题时具有良好的性能。  相似文献   

7.
求解多目标job-shop生产调度问题的量子进化算法*   总被引:2,自引:2,他引:0  
基于量子计算理论和进化理论,提出了用于多目标job-shop优化的量子进化算法(QEA-MOJSP)。QEA-MOJSP采用量子比特来表示工序对加工顺序的优先概率,利用量子叠加和相干机理,通过更新和交叉操作完成进化过程。对所有机器上工序对优先概率进行观测可得到一个调度方案,修补算子被用于不可行调度方案的修补。设计了局部搜索算子用于开采当代最优个体周围的解空间,以提高算法的收敛速度。实验结果表明,对于测试算例,QEA-MOJSP的解接近Pareto最优解集前沿,并具有很好的多样性。  相似文献   

8.
基于多色集合理论的印刷工艺规划建模研究   总被引:2,自引:0,他引:2  
罗如柏  周世生 《计算机应用》2009,29(7):1970-1973
在研究印刷工艺的加工需求和加工工序的基础上,将计算机辅助工艺设计引入印刷制造系统,并应用多色集合理论建立印刷工艺规划的数学模型,提出了一种基于此模型的印刷工艺路径求解算法。此数学模型包括围道矩阵和多色图两部分。围道矩阵描述了印刷工序实现印刷加工需求的关系,多色图描述了印刷工序的相互作用。该算法便于计算机编程的实现,能根据印刷加工需求搜索所需的工艺算子,然后求解出印刷品的印刷工艺路线。最后,通过简例分析,对所提出的模型与算法进行了验证。  相似文献   

9.
文章研究了Grover量子搜索算法,该算法进行o(N√)次搜索后只能以大于0.5的概率获得正确结果,并且没有确定最佳的搜索次数。针对这两个问题,提出了一种确定搜索次数的计算方法,使Grover算法逼近全概率地获得搜索目标。仿真结果表明,该计算方法行之有效。  相似文献   

10.
航空发动机装配工序数量多、工序间装配约束复杂. 当产品需求变化时, 人工调整存在响应速度慢、装配效率低等问题. 以最小化产品完工成本、工序提前期惩罚成本及班组重构成本加权和为目标, 建立了航空发动机装配线调度和装配班组自重构优化模型. 提出一种新的基于工序局部最优排序的分解算法, 将调度问题分解为单个装配组上工序顺序优化问题. 设计了一种工序后向插入搜索策略. 最后提出装配线调度及自重构集成优化算法. 通过数值试验,验证了模型与算法的有效性.  相似文献   

11.
Invertible Bloom Lookup Tables (IBLTs) have been recently introduced as an extension of traditional Bloom filters. IBLTs store key-value pairs. Unlike traditional Bloom filters, IBLTs support both a lookup operation (given a key, return a value) and an operation that lists out all the key-value pairs stored. One issue with IBLTs is that there is a probability that a lookup operation will return “not found” for a key. In this paper, a technique to reduce this probability without affecting the storage requirement and only moderately increasing the search time is presented and evaluated. The results show that it can significantly reduce the probability of not returning a value that is actually stored in the IBLT. The overhead of the modified search procedure, compared to the standard IBLT search procedure, is small and has little impact on the average search time.  相似文献   

12.
基于思维进化的MEBML算法的收敛性研究   总被引:3,自引:0,他引:3  
针对基于思维进化的机器学习(MEBML)的马尔可夫链的分析,证明了离散状态下趋同操作的群体信概率1收敛到全局最优状态,但由于趋同操作的局部性,从局部最优状态转移到全局最优状态的概率非常小,要增加这种转移概率,需要引进异化操作,通过P-最优状态和吸引域的概念,分析了趋同操作、异化操作的理论和实际意义。  相似文献   

13.
In an intermittent production system (IPS), a number of normal machines in a workstation may present multiple levels owing to maintenance, possibility of failure, etc. It means that the number of machines in each workstation is stochastic. This paper proposes a key performance index (KPI), which reflects the probability that an IPS can complete demand d within time constraint T. Such a probability is defined as system reliability. The IPS is modeled as a stochastic network, in which each arc is regarded as a workstation with stochastic number of normal machines, and each node is represented as a buffer. The concept of minimal machine vector (MMV), which indicates the minimal capacity required at each workstation to satisfy the demand and time constraints, is presented for evaluating the system reliability. In particular, a novel algorithm based on depth-first search is proposed to derive all MMVs. This algorithm avoids searching for unnecessary child nodes, and thus increases efficiency. Two practical examples, a printed circuit board and a footwear manufacturing systems, are used to illustrate the proposed algorithm. Such a KPI can provide information to production managers to understand the probability that an order can be completed on time.  相似文献   

14.
针对现有催化裂化(FCC)装置操作优化中未根据市场需求考虑多产品收率约束的问题,本文提出了一种求解多产品收率约束催化裂化反再系统操作优化的改进差分进化(iDE)算法.首先针对FCC操作优化中约束多和不同操作变量的可行范围差异大的特点,设计了一种协同交互变异策略产生变异个体,以提高算法的开发和探索能力;其次提出了一种具有修复功能的参数自适应策略来更新变异因子和交叉因子.此外考虑到FCC操作优化具有时效强的特点,提出了对每一代种群中最好个体实施加强搜索的方法,以提高算法的收敛速度.仿真结果表明:在求解多产品收率的FCC反再系统操作优化问题上,该算法具有较强的全局寻优能力、鲁棒性以及较快的收敛速度.  相似文献   

15.
The purpose of this paper is to describe the implementation and testing of the tabu cycle method and two variants of the conditional probability method. These methods were originally described in Glover and Laguna [Tabu search. Boston: Kluwer Academic Publishers; 1997] but have been largely ignored in the tabu search literature. For the purpose of testing, we employ a single-attribute implementation of a short-term memory procedure for the solution of a single machine scheduling problem. Computational experiments that employ instances with up to 200 jobs reveal the usefulness of the tabu cycle and the conditional probability methods as viable alternatives for managing the short-term memory in a tabu search implementation.  相似文献   

16.
In this paper, a comprehensive mathematical model is proposed for designing robust machine cells for dynamic part production. The proposed model incorporates machine cell configuration design problem bridged with the machines allocation problem, the dynamic production problem and the part routing problem. Multiple process plans for each part and alternatives process routes for each of those plans are considered. The design of robust cell configurations is based on the selected best part process route from user specified multiple process routes for each part type considering average product demand during the planning horizon. The dynamic part demand can be satisfied from internal production having limited capacity and/or through subcontracting part operation without affecting the machine cell configuration in successive period segments of the planning horizon. A genetic algorithm based heuristic is proposed to solve the model for minimization of the overall cost considering various manufacturing aspects such as production volume, multiple process route, machine capacity, material handling and subcontracting part operation.  相似文献   

17.
A consumer demand that presents auto-correlated components is a class of demand commonly found in competitive markets in which consumers may develop preferences for certain products which influence their willingness to purchase them again. This behavior may be observed in inventory systems whose products are subject to promotion plans in which mechanisms that incentivize the demand are implemented. Inventory systems that ignore these dependency components may severely impair their performance. This paper analyzes a stochastic inventory model where the control review system is periodic, is categorized as a lost-sale case, and is exposed to this class of auto-correlated demand pattern. The demand for products is characterized as a discrete Markov-modulated demand in which product quantities of the same item may relate to one another according to an empirical probability distribution. A simulation-based optimization that combines simulated annealing, pattern search, and ranking and selection (SAPS&RS) methods to approximate near-optimal solutions to this problem is employed. Lower and upper bounds for a range of near-optimal solutions are determined by the pattern search step enhanced by ranking and selection—indifferent zone. Results indicate that inventory performance significantly declines as the autocorrelation increases and is disregarded.  相似文献   

18.
面向移动终端的统计机器翻译需求越来越多,但无浮点运算单元的处理器限制了翻译速度。该文提出了一种对统计机器翻译解码运算的定点化运算方法,缓解了无浮点运算单元的处理器对翻译速度的影响。基于PC和移动终端的实验表明,在保证翻译质量的情况下,利用定点处理浮点运算的解码器的运算速度较编译器模拟的浮点运算速度提高135.6%。因此,该方法可以有效地提高浮点运算能力薄弱的移动终端统计机器翻译速度。  相似文献   

19.
针对流程工业需求和产率不确定性问题,提出了一种基于仿真优化架构的调度问题求解方法,调度方案包括生产装置加工量和加工方案的确定,以及装置间侧线分流点系数的规划。建立了带有不确定性概率分布的调度仿真模型,在此基础上,根据流程工业生产调度的特点,应用多种群遗传算法搜索优化方案。并以某炼厂为例,结果表明此方法具有良好的鲁棒性。  相似文献   

20.
汉字异或动态散列分组查找算法   总被引:1,自引:2,他引:1  
本文根据汉字内码特点,提出一个适合汉字信息处理用的汉字动态散列分组查找算法。该算法采用简单的异或散列函数将汉字进行分组,组内取链式结构顺序查找。由于散列均匀,其渐近时间复杂度为O (1) 。  相似文献   

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